Experimental observation of oscillating and interacting matter wave dark solitons

TL;DR

This paper experimentally studies the creation, oscillation, and interaction of matter wave dark solitons in a Bose-Einstein condensate, confirming theoretical predictions and analyzing effects of system dimensionality.

Contribution

It demonstrates the generation and dynamics of dark solitons in a crossover regime between 1D and 3D, providing experimental validation and developing an effective particle model.

Findings

Oscillation frequencies match Gross-Pitaevskii simulations.

Deviation from asymptotic frequency predicted by dimensionality and interactions.

Observation of soliton interactions in a controlled experimental setup.

Abstract

We report on the generation, subsequent oscillation and interaction of a pair of matter wave dark solitons. These are created by releasing a Bose-Einstein condensate from a double well potential into a harmonic trap in the crossover regime between one dimension (1D) and three dimensions (3D). The oscillation of the solitons is observed and the frequency is in quantitative agreement with simulations using the Gross-Pitaevskii equation. An effective particle picture is developed and reveals that the deviation of the observed frequencies from the asymptotic prediction $\nu_{z}/\sqrt{2}$, where $\nu_{z}$ is the longitudinal trapping frequency, results from the dimensionality of the system and the interaction between the solitons.